#include <bits/stdc++.h>

using namespace std;

const int N = 1000000 + 10; 

long long sgt[N*4];//线段树 
int a[N];

void build(int index, int begin, int end) {
	if (begin == end) {
		sgt[index] = a[begin];
		return;
	}
	int mid = (begin + end) / 2;
	build(index * 2, begin, mid);
	build(index * 2 + 1, mid + 1, end);
	sgt[index] = max(sgt[index*2] , sgt[index*2+1]);
}

void update(int index, int begin, int end, int i, int x) {
	if (begin == end){
		sgt[index] += x;
		return;
	} 
	int mid = (begin + end) / 2;
	if (i <= mid) update(index * 2, begin, mid, i, x);
	else update(index * 2 + 1, mid + 1, end, i, x);
	sgt[index] = max(sgt[index*2] , sgt[index*2+1]);
}

long long query(int index, int begin, int end, int left, int right) {
	if (begin == left && end == right) return sgt[index];
	int mid = (begin + end) / 2;
	if (right <= mid) return query(index * 2, begin, mid, left, right);
	else if (left > mid) return query(index * 2 + 1, mid + 1, end, left, right);
	else return max(query(index * 2, begin, mid, left, mid) , query(index * 2 + 1, mid + 1, end, mid + 1, right));
}

int main() {
	int n, q, op, i, x, l, r;
	scanf("%d %d", &n, &q);
	for (int i=1; i<=n; i++) scanf("%d", &a[i]);
	build(1, 1, n); 
	while (q --) {
		scanf("%d", &op);
		if (op == 2) {
			scanf("%d %d", &i, &x);
			update(1, 1, n, i, x - a[i]);
			a[i] = x;
		}
		else {
			scanf("%d %d", &l, &r);
			printf("%lld\n", query(1, 1, n, l, r));
		}
	}
	return 0;
}

求助，只过了一个点